Set trigger mechanism for firearms



June 5, 1951 `M. H. CANJAR SET TRIGGER MECHANISM FOR F'IREARMS Filed Jan. 24, 1948 '/I//l//l IN VEN TOR.

/ WHEW/ CANJAR ATTORNE Y Patenteci .une 5, 9

UNITED STATES PATENT OFFICE 2,556,025 SET TRIGGER MECHANISM FOR FIREARMS Mathew H. Canjar, Denver, Colo.

Application January 24, 1948, Serial No. 4,199

9 Clams. 1

This invention relates broadly to firearms and particularly to an improved trigger mechanism.

Expert marksmanship requires a trigger mechanism that is reliable and which can be adjusted to suit the taste of the marksman.

It is Well understood among marksmen that the set of the trigger is' often the determining factor in extreme accuracy and for this reason each marksman tries to adjust the set of the tri gerso as to obtain the best results. In some cases marksmen prefer whatis popularly referred to as a "hair trigger that is one that requires merely a light'touch in order to release the bolt or hammer. For ordinary Shooting, however, a "hair trigger" adjustment is not necessary and might be a source of danger.

It is the object of this invention to produce a trigger mechanism that can readily be substituted for the standard trigger supplied with commercial ries and which shall be of such construction and design that it will operate in the same way as the trigger that it replaces and which, in addition, can be adjusted' to obtain a "hair trigger" eect.

Another object is to produce a trigger mechanism of such Construction that the pull required can be adjusted between considerable limits, thereby making it possible for the marksman to effect adjustments best suited to his taste.

A further object is to produce a set trigger mechanism that can be easily sealed in inoperative position in cases where the contest rules require only the original trigger to be used.

The above and any other objects that may appear as the description proceeds are attained by means of a Construction and an arrangement of parts that will now be described in detail and for which purpose reference will now be had to the accompanying drawing 'in which the invention has been illustrated and in which:

Figure 1 is a view, partly in section, showing a well known trigger mechanism provided with the set' trigger to which this invention relates;

Figure 2 is a View showing how the trigger mechanism may be applied to a firearm having a hammer instead of a bolt;

Figure 3 is a section taken on line 3-3, Figure 6;

Figure 4: is a. section taken on line 4-4, Figure 6;

Figure 5 is a section taken on line 5-5, Figure 6;

Figure 6 is a parti al vertical longitudinal section on an enlarged scale of the trigger mechanism of Figure 1; and

Figure 7 is a rear elevation, looking in the direction of arrow 1, in Figure 6.

In the drawing reference numeral o designate the gunstock which may be of wood. Percussion release means H is pivoted at !2 and is provided with a sear nose !3 that supports the rocking lever [4 when the gun is cocked. The extent of the overlap of parts l3 and M may be adjusted by screw !5. Spring !6 acts on percussion release means Il exerting thereon a force tending' able interconnection between such set trigger and the percussion release sear may be employed.

The ordinary trigger employed with this type of rifie terminates at its lower end in a curve'd finger piece. In the improved trigger Construction that forms the subject of this invention, percussion release means I l terminates at IT and the rearwardly and downwardly ranging part |8 is provided with an opening for pivot pin !9 that secures the trigger body 20 to part |8 of the percussion release means. The under side of part IB is provided with a transverse notch 2l.

The trigger body is arcuate and forwardly concave, the' center of curvature being indicated by numeral 22. The exact curvature is not important. A slot whose bottom has been designated by numeral 23 and whose side Walls have been designated by numerals 24, is milled in the upper end of the trigger body; the width of the slot is such that it will receive the lower portion of part [8. Walls 24 have openings for the reception of pivot pin I& about which the trigger body rocks. A narrow slot 25 is milled in the back of the trigger body and this extends entirely through the body below point 25. A set trigger 2'6 of a shape substantially like that shown in Figures 1 and 6, is positioned in slot 25 and is mounted for limited rocking movement about pivot 21. An adjusting screw 28, having a, tapered end 29, is threadedly connected with the wall of'opening 30, one end of which is provided with internal threads for engagement with the threaded portion of the screw. The conical or tapered'end of the adjusting screw serves as a stop for limiting the forward movement of the set trigger as clearly shown in Figure 4. It will be observed that the set trigger has a cutout or notch in its front edge, which notch has been designated by numeral 3l. The lower end of the set trigger extends forwardly to such an extent that it projects some distance to the front of the trigger body when it is in engagement with the adjusting screw 28, in a manner shown most clearly in Figu're 6. A pin 32 is positioned in openings in'the trigger body and extends across slot 25. A spring 33 is wound one or more turns about pin 32 and has its lower end bent laterally into a position to overlap the adjacent trigger body as indicated by reference numeral 34. The upper end of the spring rests on the rear edge of set trigger 26 and is so wound about pin 32 that it normally holds the set trigger in engagement with the adjusting screw in the manner shown in Figure 6. The upper end of the set trigger has an upwardly extending sear nose 35 that is positioned in notch 2l when the set trigger is in normal or unset position (see Fig. 1). When the trigger body is moved forwardly, spring 33 will rock the set trigger into a position in which the sear 35 laps the under surface of part 36, the extent of this overlap being determined by the position of the adjustng screw 28. When the gun is cocked and the set trigger is in the position shown in Figure 6, a comparatively small pressure exerted on the set trigger will rock it suficiently to bring sear 35 into register with notch 2l, whereupon spring 31 functions to rock the trigger body counterclockwise until the parts reach the position shown in Figu'e 1; the resultant hammer blow or impact serving to rock percussion release means ll about its pivot sufiiciently to release the firing pin.

The force necessary for releasing the set trigger and the angular movement thereof necessary to disengage the sear 35 from the surface of 36 can therefore be adjusted by the screw 28; by

' turning this screw in either direction, a correhammer gun; the hammer has been designated by-reference numeral 38 and the hammer spring by freerence numeral 39.

With the parts in the position shown in Figure 1 the trigger operates in the usual way. When the set trigger is to be used, the trigger body is pushed f orwardly until the set trigger moves into the position shown in Figure 6.

-I n shooting matches where a set trigger is not permissible, pivot 21 may be removed, thus makingthe set trigger mechanism inoperative. If necessary the pivot 21 can be replaced by a fine wire-seal to insure the set trigger mechanism being made inoperative to comply with certain Shooting match rules. V From the above it will be seen that the trigger mechanism to which this invention relates is very simple, and that it consists of two major parts; the set trigger body 20 and the set trigger 26. In addition to the two principal parts, there are the four pivots and spring 33. The assembly is attached to part !8 of the percussion release means and the trigger body acted on by spring 31.

Since percussion release means H is substantially identical with the one provided in the original gun mechanism down to and including part of la, it is evident that the set trigger assembly which includes the percussion release means and set trigger can be substituted for the usual percussion release means and trigger without making any changes in the lock mechanism of the gun. This trigger assembly can be sold as a unit and installed by any gunsmith.

Having described the invention what is claimed as new is:

1. In a trigger mechanism, percussion'release means, a trigger body pivoted upon the release means for limited rocking movement, spring impelling means interposed between the release means and the trigger body for normally holding the trigger body in a predetermined position relative to the release means, means comprising a set trigger pivcted on the trigger body, and ccoperable sear means on the set trigger and release means for holding the trigger body in a displaced position against the action of the spring, release of the sear means by the set trigger eifecting return of the trigger body to its normal position, imparting to the release means a hammer blow actuating the same.

2. In a trigger mechanism, percussion release means having an upwardly ranging portion having a sear thereon and a rearwardly ranging lower end, the upwardly ranging portion having an opening for the reception of a pivot, a trigger body pivotally connected with the rearwardly ranging end, for limited rocking movement, a compression spring positioned between the rearwardly ranging end and the trigger body at a point to the front of the pivotal connection, the force exerted by the spring serving to normally hold the trigger body in its rearmost position, and means comprising a settrigger carried by the trigger body, cooperable sear means on the set trigger and rearwardly ranging lower end for holding the trigger body in a forward position against action of the spring, the release of the cooperable sear means by the set trigger e'ecting release of the trigger body, whereby the latter will move rearwardly imparting to the percussion release means a hammer blow actuating the same. V

3. In a trigger mechanism for a firearm, a manually actuated percussion release means for eifecting the firirg of the firearm, and means for actuating said release means by a hammer blow comprising, a trigger body pivoted to the release means for limited rocking movement, the trigger body being concave on its front side forming a nger piece, means comprising a spring interposed between the release means and the 'trigger body for normally holding the trigger body in its rearmost position, means comprising a set trigger pivoted to the trigger body, cooperable sear means on the set trigger and release means for holding the trigger body in a forwardly adjusted position against the action of the spring, release of the cooperable sear means by the set trigger efrecting return of the trigger body to its normal position in response to the action of the spring, imparting to the release means a hammer blow actuating the same.

4. In a trigger mechanism for a firearm, percussion release means for controlling the firing of the firearm, a trigger body pivotally connected with the release means for limited rocking movement, means comprising a compression spring interposed between the release means and the trigger body, on one side of the pivot, for normally holding the trigger body in a predetermined position relative to the release means, and means comprising a set trigger pivoted to the trigger body having a portion adapted to hold the trigger body ina position displaced from normal.

5. In combination with percussion release means mounted for pivotation, a trigger assembly comprising, a trigger body having a notoh in its npper end for receiving an end of the release means, the sides of the body lapping the release means and having openings for a pivot pin, apivot pin extending through said openings and through the release means, spring means interposed between the release means and the trigger body for normally holding it in its rearmost position, the trigger body having a limited rocking movement about its pivot, said trigger body havin a slot extending from the notch to its lower end, the lower end of the notch eX- tending entirely through the body, a set trigger positioned in the slot and pivotally .connected with the trigger body, the lower end of the set trigger having a finger grip portion extending to the front of the trigger body, spring means in terposed between the trigger body and the set trigger normally urging the finger grip portion of the set trigger forwardly, and means oomprising the set trigger for holding the trigger body in a forward position against the action of the first named spring.

6. In a firearm having settable percussion means which fires a Cartridge upon its release, a settable member movably mounted on the firearm adapted to release the percussion means, a second member operably connected to the settable member and having limited movement relative thereto, a set trigger mounted for movement on the second member, the set trigger and settable member having cooperable sear means, spring means urging the second member in such direction that upon release of the sear means by the set trigger, the relative movement between the second member and first member imparts an impact to the first member to release the percussion means.

7. A device in accordance with claim 6 wherein the second member is the main trigger of the firearm.

8. A device in aoeordance with claim 6 wherein the set trigger is adjustably mounted on the second member to various fixed positions in a manner such that the degree of overlap of the sear means may be adjusted, whereby the sear may be released with difierent desired anplitiides of movement of the set trigger.

' 9. In a trigger mechanism for a firearm of the type having percussion release means, a trigger body mounted on a portion of the release means and having limited relative movement thereto, spring means for impelling the trigger body in the direction of trigger pull, the trigger body when impelled to the limit of relative movement by the spring means being adapted to impart an impact to the release means to actuate same, a set trigger mounted for movement relative to the trigger body, sear means actuable by the set REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATEN'I'S Number 

